The Role of Deep, Moist Convection and Diabatic Heating In Association With A Rapidly Intensifying Cyclone: A QG/PV Analysis

After a long hiatus, I have returned with a new article (finally). I continue my discussion on PV dynamics (I am always learning something new each day), but this time focus more on PV non-conservation. My motivation for this case study/paper came from a challenging winter storm we had to deal with at the North Platte WFO. Numerical models poorly simulated the rapid intensification of a cyclone ejecting the Rockies, and the event ended up being a local high impact storm for the CWA. It was also a null event across portions of North Dakota as the cyclone rapidly intensified and stalled. The culprit for rapid intensification was the initation of deep, moist convection near the center of the cyclone/warm front and the generation of low level PV through differential diabatic heat release which influenced the low level mass fields and advection patterns. It was a unique case study, and I hope it is of use to other forecasters/weather enthusiasts out there. Please take the time to closely view the images (the small details made all the difference in this event!), especially the “dprog/dt” analyses of PV generation/destruction. The link is the local office case study (still in review by my SOO) in .pdf format (6 MB’s). As always, any questions/comments/criticism/feedback are always welcome.

My next article, I hope, will stray away from rapid cyclogenesis and delve into “negative” feedbacks to cyclone development–a forecast which can be equally as challenging as rapid positive feedback cyclogenesis.

Also, take a look at the references. The Brennan paper on PV non-conservation is superb.

One response to “The Role of Deep, Moist Convection and Diabatic Heating In Association With A Rapidly Intensifying Cyclone: A QG/PV Analysis”

I have several questions. After reading the research paper, I am still confused. One of my first questions is how does the diabatically-induced PV anomaly at the low levels enhance the low level mass and wind fields (does it create pressure falls, etc. ?). My second question: When the low level and upper level PV anomalies couple, how do they produce intense vertical motion? My third question: I have seen several storms where this kind of rapid cyclogenesis was possible. Why did they not happen like this storm did? My final question: What processes interfere with the rapid cyclogenesis and tropopause folding? How do we observe these interferences?
Thanks for your consideration. You have a wonderful blog that has incredibly insightful information for me.